When we are young and healthy, free of disease and saggy bits, our DNA, which forms the building blocks of life, is healthy and functions as smoothly as a newly serviced car.
The DNA molecules in the nucleus of every cell are bombarded by baddies. Some are from the environment and some are from inside our bodies – and either way, these assaults cause some of the important bonds in these molecules to break.
The good news is that every cell in our bodies has a full army of enzymes available to counteract these breaks, and to repair the DNA. But the bad news: when the damage happens at a faster pace than the repair, the harm become apparent. So as the years creep on, much depends on just how our DNA manages to repair the damage effectively, and in time.
The popular US science magazine, Scientific American, summed it up well when it described ageing as the result of “…the accumulation of random damage to the building blocks of life… that begins early in life and eventually exceeds the body’s self-repair capabilities…”
Science fights back
Happily, scientists have accumulated the evidence required to connect many of the dots between random damage, DNA, the body’s self-repair capabilities, degenerative disease and ageing.
They have found that while we cannot stop the creep of time we can do something about how we age.
Researchers have found that several factors play a role in the random damage to DNA, and that there is a protein complex – called NFkB (Nuclear
Factor kappa B) – which takes centre stage in controlling the damage. NFkB regulates a variety of cellular responses, including immune and inflammatory responses, cell survival and cell protection.
It is when the NFkB misfires that things go wrong, and we could be looking at cancer, rheumatoid arthritis, artherosclerosis, diabetes, inflammatory and auto-immune diseases, viral infections, ageing and a growing list of disorders.
The world takes notice
Dr Nicholas Perricone, whose patient list includes Hollywood stars like Jennifer Lopez and Bruce Willis, is one of the US’s prominent anti-ageing practitioners.
Some years back, he produced a work entitled “Inflammation Theory of Ageing”. Suddenly, Oprah (and thus the world) took notice of just how damaging inflammation can be on cell survival. The Perricone Diet, which promotes the avoidance of foods that cause a spike in blood sugar levels, is based on his theory.
So, if we know so much, just how does ageing, the result of insufficient DNA repair, come about? Here’s how it happens:
The four steps in DNA damage and ageing
Visualise the processes involved in ageing as four (ultimately fatal) strikes by the enemy.
Strike 1 = Random day-to-day DNA damage.
This is caused by oxidative stress (leading to increased levels of free radicals), environmental pollution, ultraviolet rays, cigarette smoke, trans fatty acids and other unhealthy ingredients in your diet, exercise, stress and other factors.
Strike 2 = Ineffective DNA repair mechanisms.
A powerful set of enzymes such as endonucleases, exonucleases, polymerases and ligases work together 24/7 to remove harmful lesions in DNA, caused by the above as well as metabolic mistakes. As long the repairs happen as quickly as the damage occurs, you stay healthy and free of disease.
But this doesn’t happen. The rate of DNA repair is now known to be a reliable predictor of your lifespan. Scientists have repeatedly been able to demonstrate that an animal’s lifespan is predicted by its ability to carry out DNA repair.
Rodents, for example, live only a couple of years compared to humans, who manage to reach 90 years quite easily. Humans also have 16 times the DNA repair capacity of rodents.
The reason slowing repair functions matter, is because if DNA damage exceeds the rate of self-repair, DNA lesions will be copied to the next generation of cells. With each subsequent cell division, these lesions will be copied into the next cell, and the next, creating a proliferation of cells with DNA defects.
Strike 3 = Defective DNA may lead to, or trigger unwanted processes.
Even the slightest change to the DNA may have an effect on the body, usually in the form of disease.
Since DNA has a very specific sequence of nucleotide building blocks, which provide very specific codes for very specific proteins, the loss or addition of one single nucleotide, due to insufficient repair, may change the code completely.
This may lead to the non-production of an essential protein or substance, or it may activate dormant, malignant cellular processes.
Strike 4 = One such an effect is the aberrant activation of NFkB.
We know NFkB is the key regulator of a variety of cellular responses listed above, as well viral infections, ageing or any of a growing number of disorders. If NFkB in the skin is activated after sun exposure, wrinkles will follow, even melanoma. If it is activated in the lungs after exposure to cigarette smoke, emphysema or lung cancer may follow.
What can you do?
There are many preventative measures: stop smoking, avoid foods that contain “bad” fats (saturated and trans fats), take supplements to limit the creation of free radicals in your body when exercising, use sunblock to protect your skin against UV-exposure.
The ultimate step, of course, would be enhanced DNA repair which would automatically lead to NFkB inhibition. Massive amounts of money is being thrown at research in an ongoing attempt to create a product to stop the clock and prevent the diseases of ageing.
False promises abound. Only when science can explain and show that a product can lead to DNA repair, and find ways to measure the extent of this repair in DNA trials, can they actually claim they have decoded the mechanism to halt ageing.
The truth is the ageing process is not yet fully understood and scientists have yet to discover the magic formula to keep us youthful and vital.
“Anti-ageing medicine has become a fast-growing discipline and will be the medicine of the future,” says Dr Geraldine Mitton, an integrated medicine and anti-ageing practitioner based in Cape Town. In her book, Dr Geraldine Mitton’s Anti-Ageing Handbook – Practical Steps to Staying Youthful, she says the trick is to concentrate on extending our healthspan rather than our lifespan.
“Essentially, what we want is to live healthily, with a good quality of life, for as long as possible.”
Nutrition to stay young
- (Mari Hudson, Health24)